1. Field of the Invention
The invention relates to a valve provided in an endoscope that controls a flow of fluid.
2. Description of the Related Art
An endoscope comprises a fluid supply line that carries fluid to a distal end of the endoscope and an inhalation line that carries various matter from the distal end. An endoscope valve is provided in the fluid supply line and the inhalation line, and controls the flow of fluid.
The endoscope valve mainly comprises a cylinder and a piston that is inserted into the cylinder. The cylinder and piston can be disassembled for maintenance or to be sterilized. A construction that installs the piston into the cylinder is disclosed in Japanese Publication of Unexamined Patent Application (HEI)5-95897 and Japanese Publication of Unexamined Patent Application 2009-201845. Japanese Publication of Unexamined Patent Application (HEI)5-95897 discloses a construction that engages a projection provided on a circumferential surface of the piston with a groove provided on an inner circumferential surface of a cylinder. Japanese Publication of Unexamined Patent Application 2009-201845 discloses a construction that inserts a projection provided on a circumferential surface of the piston into a guide groove provided completely around an inner circumference of a cylinder. The piston comprises a deformable plastic member. The projection and its circumference deform so that the projection moves into the groove in the cylinder. A construction that detaches the piston from the cylinder is disclosed in Japanese Publication of Unexamined Patent Application (HEI)5-95897. It discloses a construction in which a cam provided in the piston moves along a cam groove provided in the cylinder, so that the piston moves in the direction to which the piston comes off the cylinder.